Marine boiler with double circulation and steam-superheater.



J B. PRUDHGN. MARINE BOILER WITH DOUBLE CIR GULATION AND STEAM SUPERHEATBE. APPLIDATION FILED MAY 19, 1913,

Patsmfied Jam. 26, 1915.

THE NORRIS PETERS cm, PHDTOLITHO.. \VASHINGRJN. D. c

tubes 0.

J EAN BAPTISTE PRUDHON', 0F MARSEILLE, FRANCE.

MARINE BOILER WITH DOUBLE CIRCULATION AND STEAlVI-SUPERHEATER.

mentors.

Specification of Letters Patent.

Patented Jan. 26, H5.

Application filed May 19, 1913. Serial No. 768,575.

To all whom it may concern:

Be it known that I, JEAN BAPTISTE PRUD- non, residing at 47 Rue du Coq, Marseille, Bouches-du-lthone, France, have invented a certain new and useful Marine Boiler with Double Circulation and Steam-Superheater, of which the following is a specification.

This invention has reference to a double circulation marine boiler with steam superheater situated in the top of the fire-box which is formed by bricks with air grooves surrounded by sheet iron.

This boiler is shown in the accompanying drawing. I

Figure 1 shows the boiler in two half cross sections, that on the left being along the line AB of Fig. 2, whereas that on the right is along the line CD. Fig. 2 is a longitudinal section of the same. Figs. 3 and 4 are vertical and horizontal sections of a portion of the wall of the fire-box.

The cylindrical boiler consists of a steel envelop a, of two furnaces b and of smoke The fire-box situated at the back comprises four large pipes d, al three of these pipes d are situated in the upper portion and their axes pass slightly above the level of the Water in the boiler. The fourth pipe (Z1 is situated in the lower portion of the boiler between the two furnaces. The upper pipes d and the lower pipe (Z are connected together by bundles of curved tubes 6. The lower pipe d toward the back at the upper portion has a rectangular pipe 7 connected to the upper pipes cl by tubes 2' arranged in the form of a fan, against the bottom of the fire-box. This arrangement is for preventing the reverberation of the brick bottom of the fire-boX against the smoke tubes 0 and to protect their connection to the head plate. The fire-box is surrounded by sheet metal 7s lined at the interior with special fireproof bricks Z having passages forming an air mattress. They are situated along two superimposed rows covered over with fireproof bricks m which are for their part surrounded by the metal sheet 70.

The superheater arranged in the top of the fire-box consists of three rectangular iron pipes a, a a which are connected together by curved hanging tubes 0 of U- shape. It results from this arrangement that the steam introduced through one of the extremities of the pipe 10. after having passed through the tubes 0 enters the pipe 11.

and then a and passes out through the end opposite to the entrance of n.

In the tubular bundle c a free space p without tubes is provided in the center and above each furnace which assists the passage of the steam abundantly produced by the furnaces and forming the ascending circulation, the descending circulation being naturally effected between the bundles of tubes 0 and against the sides of the envelop. The water descends directly to the pipe (Z communicating with the base of the boiler and then rises up through the tubes 6 and 2', which forms a double descending circulation. The tubes 6 and '21 when lighting the fire rapidly evaporate the water contained in the tubes and the steam formed passes into the upper pipes (Z and from there into the steam reservoir. The evaporated water is substituted by water coming from the bottom of the boiler from which results a lively circulation. Above the pipes (Z and at the interior of the boiler a baffle plate r is arranged which prevents the projections of steam coming from tubes e situated near the openings of these pipes d. This very definite double circulation enables the boiler to produce a great quantity of steam per sq. meter and under the best conditions. It thus results that the dimensions of the boilers may be decreased. The double circulation thus effected also permits of effecting a noticeable economy in fuel.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. A marine boiler comprising a casing, two furnaces therein, horizontally-arranged smoke tubes 0, in the casing, a plurality of tubes (Z, arranged horizontally in the upper portion of said casing, a single tube (Z arranged horizontally in the lower portion of said casing between the furnaces, curved tubes 6, connecting the said upper tubes d, with the said lower tube (P, a pipe f, arranged transversely at the rear of and above the said lower pipe (Z and communicating with the latter and curved tubes i, connecting the pipe f, with the tubes (Z, said tubes 0, being arranged to form a free space above each furnace, for the purpose specified.

2. A marine boiler comprising a casing, two furnaces therein, horizontally-arranged smoke tubes 0, in the casing, a plurality of tubes cl, arranged horizontally in the upper portion of said casing, a single tube (Z arranged horizontally in the lower portion of said casing between the furnaces, curved tubes e, connecting the said upper tubes cl, with the said lower tube (P, a pipe f, arranged transversely at the rear of and above the said lower pipe (Z1 and communicating with the latter, curved tubes 2', connecting the pipe f with the tubes d, said tubes 0,

being arranged to form a free space above each furnace, and a baffle plate 1", arranged above the tubes d, and extending transversely of the casing.

In testimony whereof I afiix my signature in presence of two witnesses.

JEAN BAPTISTE PRUDHON. Witnesses M. ESQUERRI, VON PALMAS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

